Based on those common allegations, plaintiffs stated separate claims for
trespass and nuisance. In their trespass claim, they alleged that they had legal possession
and control of their property and that they did not authorize the entry "of any trees, roots,
or vegetation of any kind onto their land from defendants' land." In their nuisance claim,
plaintiffs alleged that the roots "have severely and unreasonably invaded plaintiffs' land"
and that the invasion "has interfered with plaintiffs' ability to use and enjoy their land" as
a result of the damage to their house. Plaintiffs did not allege in either claim that
defendants acted with any specific level of culpability or that they were engaged in an
ultrahazardous activity.

To place the parties' arguments on appeal in perspective, we begin with an
examination of the common law principles at play in this case. As discussed, plaintiffs'
complaint separately states claims for trespass and nuisance. Each of those theories of
liability involves a different kind of interference with plaintiffs' interest in their land:
"[A]n actionable invasion of a possessor's interest in the exclusive possession of land is a
trespass; an actionable invasion of a possessor's interest in the use and enjoyment of his
land is a nuisance." Martin et ux v. Reynolds Metals Co., 221 Or 86, 90, 342 P2d 790
(1959), cert den, 362 US 918 (1960). Courts in some jurisdictions have concluded that
tree roots or branches that intrude into or over neighboring lands may be either a trespass
or a nuisance; courts in other states have rejected liability under either theory. However,
the issue is one of first impression in Oregon. The parties discuss the competing
approaches that other courts have taken, both sides urging that we adopt the approach that
is beneficial to their respective positions. We discuss three exemplary cases.

In Michalson v. Nutting, 275 Mass 232, 175 NE 490 (1931), the plaintiffs
alleged that roots from a neighboring poplar tree had clogged their sewer pipes and grown
under their cellar, causing them expenses for unclogging the pipes and threatening harm
to their house. The Massachusetts court held that there was no distinction between an
intrusion by overhanging branches and one by invading roots. In either case, an owner
has the right to grow trees on its land, which naturally leads to branches and roots
crossing the boundary line. When that happens, the owner of the other land is limited to
cutting the branches and roots where they intrude. Thus, there was no actionable
nuisance. Nothing in the court's opinion suggested that the owner of the tree intentionally
or negligently caused the roots to grow onto the plaintiff's land; rather, he had simply
refused to remove them.

In Whitesell v. Houlton, 2 Haw App 365, 632 P2d 1077 (1981), the
defendant owned a banyan tree whose branches overhung the plaintiffs' property and
damaged their garage and automobile and threatened additional damage until the
plaintiffs had them cut back. The Hawaii court held that the Massachusetts rule was
unfair. "Because the owner of the tree's trunk is the owner of the tree, we think he bears
some responsibility for the rest of the tree." Id. at 367. Hawaii law had long provided
that, if the owner of a tree knows or should know that it constitutes a danger, the owner is
liable for harm that it causes on or off the property. Thus "the damaged or imminently
endangered neighbor may require the owner of the tree to pay for the damages and to cut
back the endangering branches or roots[.]" Id. at 368.

Finally, in Abbinett v. Fox, 103 NM 80, 703 P2d 177 (NM App), cert
quashed, 702 P2d 1007 (NM 1985), roots from the defendants' cottonwood tree damaged
structures on the plaintiffs' property. The New Mexico Court of Appeals discussed
Michalson, Whitesell, and a number of other cases involving invading branches and roots;
it ultimately adopted the Whitesell rule. The court held that, although landowners may
use their property in ways that maximize their own enjoyment, they may not unreasonably
interfere with the rights of adjoining landowners or create a private nuisance. The
defendants had negligently maintained their tree, damaging the plaintiff, and the appellate
court concluded that the trial court had correctly required the defendants to respond in
damages. Abbinett, 103 NM at 84-85.

Although it was not the focus of the courts' analyses, the defendants'
culpability for the intrusions was different in each of the cases that we have discussed. In
Michalson, the defendants simply planted the tree and refused to remove the roots; there
is no suggestion that they intentionally or negligently caused harm to the plaintiffs. In
Whitesell, however, the defendants knew or should have known that their tree would
cause damage to the plaintiffs' property, which in Oregon would support a finding that
they intended to cause that harm. SeeLunda v. Matthews, 46 Or App 701, 705, 613 P2d
63 (1980). In Abbinett, the trial court found that the defendants were negligent, a finding
that the appellate court affirmed.

Unlike those courts, we conclude that the issue of culpability is decisive in
this case. Thus, we do not need to decide whether we would agree with the Hawaii and
New Mexico courts if defendants had acted with some level of culpability or if they had
been engaged in an ultrahazardous activity. As we now explain, because plaintiffs do not
allege that defendants did so, they have not stated a claim for either trespass or nuisance
under Oregon law.

At common law, an unauthorized entry onto the soil of another was in itself
a trespass. Loe et ux v. Lenhard et al, 227 Or 242, 248, 362 P2d 312 (1961). Martin
appears to have applied that rule of strict liability. The court noted that, "[s]ince we hold
that the intrusion in his case constituted a trespass it is immaterial whether the defendant's
conduct was careless, wanton and willful or entirely free from fault." Martin, 221 Or at
102. However, in Loe et ux the Supreme Court adopted the rule of the first Restatement
of Torts, §§ 158, 165 (1936), that there is liability for an unintentional intrusion only
when it arises out of negligence or an ultrahazardous activity. Loe et ux, 227 Or at 248-49. Despite the contrary statement in Martin, the Loe court treated that case as involving
an intentional trespass. Id. at 248. By the time that this court decided Frady v. Portland
General Electric, 55 Or App 344, 347, 637 P2d 1345 (1981), we could summarize the
state of the law as it applied to both nuisance and trespass claims:

"In order for the law to attach liability to the operation of a purported
nuisance, the plaintiff must allege [that the] defendant's actions were
intentional, negligent, reckless or an abnormally dangerous activity.
Raymond v. Southern Pacific Co., 259 Or 629, 634, 488 P2d 460 (1971). A
trespass also requires that the intrusion be intentional, negligent or the
result of ultrahazardous activity. Martin v. Union Pacific Railroad, 256 Or
563, 565, 474 P2d 739 (1970)."

Unlike trespass, nuisance claims had long required proof of fault or ultrahazardous
activity. SeeRaymond, 259 Or 634-35, 634 n 4. Our summary in Frady remains the law
at present.

We applied those principles in Ward v. Jarnport, 114 Or App 466, 835 P2d
944 (1992), rev den, 315 Or 313 (1993). In Ward, the plaintiffs owned property downhill
from the defendants. The plaintiffs' predecessor constructed a wall along the upper
boundary of the property; the defendants' predecessor thereafter placed fill dirt in the area
behind the wall. The ultimate result was that the dirt pressed against the wall, cracked it,
and tilted it toward the plaintiffs' property. Without corrective action, the wall would
ultimately collapse. The plaintiff asserted claims for both trespass and nuisance against
the defendant, seeking to require it to abate or correct the condition. The trial court
granted summary judgment to the defendants, and we affirmed. We recognized that the
law has long held adjoining landowners liable for damage caused by fill placed against a
neighbor's wall; however, in Ward there was no evidence or allegation that the
defendants' failure to remove the dirt was negligent, reckless, or intentional. As a result,
there was no support for any theory of liability for trespass or nuisance.

In short, plaintiffs do not allege that defendants acted or failed to act with
any form of culpability, and they do not allege that they engaged in conduct that could
make them strictly liable for trespass or nuisance. As a result, they have failed to state a
claim for relief under either theory.

Affirmed.

1. Plaintiffs do not assert that the trial court denied them an opportunity to replead
their claims in an amended pleading.

2. Indeed, on the face of the pleadings, defendants appear to be less culpable than the
defendants in Michalson, who apparently refused to remove the poplar tree after learning of the
damage that it was causing and threatening to cause to the plaintiffs.